HistoryGeek2019 wrote: ↑30 Oct 2019, 19:02
Britain has the entire 500 million strong Empire backing it. Once FDR gets re-elected, it also has lend-lease aid from the United States. That is enough for Britain to wage an air and sea war against Germany indefinitely.
If Britain gains no superpower allies then Germany will either win the war or the British will make terms. The things you mention are not going to change that trajectory - Lend Lease was not sufficient and the British Empire was an anachronistic source of weakness, not strength.
How much damage can Germany inflict with each attempted Channel crossing vs. how much damage will Germany suffer? Maybe 10-20 thousand troops will get across with each attempt, with a tiny amount of tanks and artillery. They will quickly run out of supplies and surrender each time. How many casualties can they inflict when the British strategy is defensively focused (manning the GHQ Line)? Optimistically, the Germans inflict 1-3 thousand casualties with each wave before they surrender. That's a war of attrition that Germany is losing. Germany would also suffer devastating losses at sea with each attempt. Their "river barge" fleet would get wiped out on each attempt. Germany didn't have naval construction capabilities anywhere close to what Britain had. Britain could easily rebuild the few destroyers and cruisers lost in each crossing attempt faster than Germany could rebuild its entire landing fleet.
If the Royal Navy concentrates the mass of warships near the Channel needed to defeat an invasion, then in the Atlantic the Axis fleets are going wild. If it moves into the Atlantic to protect its supply lines, then it does not have the ships on alert stand by to repel an invasion. Sealion in conjunction with an Atlantic War in 1941 presents difficulties for the UK. Not in the least because the technical characteristics of a Sealion invasion in 1941 could and would be much improved over 1940.
The British were ahead of Germany in the technology of radar and radar jamming once they figured out how to counter Knickebein and Gerat during the Blitz. From that point on, the Germans could never undertake precision bombing at night. And the British quickly figured out how to engage in night-fighting during the Blitz and were inflicting significant casualties by the end. Britain was also outproducing Germany in aircraft, so trying to bomb Britain is a war-losing strategy for Germany.
The British had the significant disadvantage of being much further from Germany with their bombers from the UK than the Germans were from their targets in France. The best LW strategic targets were coastal, in order to enhance the effects of the sea campaign. Coastal targets, because they were on the coast, could be found more easily. In terms of navigation techniques, after losing the battle of the beams the Germans switched to the use of Freya radars (Egon Verfahren) for the pathfinder force. The advantage of being closer.
Taking Gibraltar and Portugal won't allow Germany to cut off British sea lanes in the Atlantic. The Royal Navy still dwarfed the KM and Italian navy, and would simply take over the Azores and Canaries.
With a Sealion massed in France in the summer of 1941 the British will need 100 destroyers and cruisers on invasion alert. These are not available for the Atlantic - if they break their alert, they cannot stop Sealion. That's the general vulnerability as I see it.
The Axis didn't have the logistics to support a stronger Africa Korps - the British had naval superiority in the Mediterranean, and nothing the Axis could do would change that.
No invasion of Russia and the Germans would have the logistics to support the AK. Not only tens of thousands of more trucks, but also large numbers of purpose built littorial transports, (Siebels, MFP's, K-ships).
The Soviet Union would not have made any more attacks after settling with Finland because Stalin didn't want to go to war with Britain and the United States. He wanted Germany to hand over Bulgaria and bases in the Balkans so that the USSR wasn't confined by the Turkish Straits. Otherwise, Stalin would have slowly improved his position as Britain and Germany bled each other dry.
Stalin was not enough afraid of the United States with the atom bomb to be deterred from China and Korea. The idea that the British Empire in 1940 caused him the slightest degree of concern is completely infeasible.
Britain far outproduced Germany in naval construction throughout the war and was better at naval technology than the Germans. With American lend-lease aid, Britain was never at any risk. U-boats were simply an outdated technology, and Dönitz was living in the past. Even modern submarines can be detected by surface ships. The British would have countered anything the Germans threw at them at sea.
The danger with the U-boats was that they might draw the US into the war. The idea that the British without the Americans could win the U-boat war is not one that would occur to me.